In my ideal world, we have a best-of-both-worlds level of centralisation, where the provincial teams have the authority to make some in-house decisions (such as coaching and player recruitment), but with a centralised skills training program, and a system for players can appeal to RA for freedom of movement to other Super teams.
RA could have some level of sway over provincial teams by managing the salary cap. They can recommend a coach (or other staff memeber) to a team, offer to pay their salary, and provide an increase to the salary cap in return for accepting the RA appointment. It would be important to say that teams cannot have their salary cap reduced for refusing an offer from RA; we want more carrots than sticks in a system that already has people angry at each other.
Players could appeal to RA to move to another team for more playing time. Their current team could block the move by guaranteeing 800 minutes a season (10 games), which would involve a salary cap penalty for failing to fulfill. Otherwise, RA then contacts the other provinces and lets them know about the official availability. The contract transfers in its existing form from one province to the other, to prevent players moving to get paid.
RA would make it known to foreign leagues that they are willing to give players a sabatical placement for 12-24 months, paying some portion of their salary during. They could offer this player to the provinces; some sort of bidding process would exist for situations with more than one team wanting the player, but otherwise it would simply be a placement. It would require that the player be given a minimum number of playing time minutes throughout the season.
The incentive in return for taking these players would be that RA would facilitate a sabatical for that province's players in future, and some salary cap benefits. Plus, a free player.
Much more detail required, but I think the big issue to sort out is freedom of movement for players, to prevent potential Wallabies from languishing on a bench somewhere.
